JPH0571067U - Tension reducer - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain a tension reducer capable of improving operability by preventing generation of abnormal noise and frictional force during operation of the tension reducer. [Structure] An outer end 20A of a weak spring 20 is locked to an adapter 16 connected to a winding shaft, and an inner end 20B of the weak spring 20 is attached to a gear spring 32.
Is locked to. Therefore, when the tension reducer operates, that is, when the rotation of the gear spring 32 is blocked and the weak spring spring 20 is opened, the weak spring spring 20 is unwound from its outer end 20A and adjacent side walls may rub against each other. Absent. Therefore, generation of abnormal noise and frictional force is prevented, and operability is improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a tension reducer, and more particularly to a tension reducer used in a webbing retractor.

[0002]

[Prior Art]

 This type of tension reducer (webbing retractor) is equipped with two types of springs, large and small. One end of the weak spiral spring is connected to the winding shaft, and the other end is connected to the strong spiral spring via a gear spring. The other end of the strong spring is locked to the case (cover). That is, the winding shaft, the weak spring, the gear spring, and the strong spring are connected in series, and the winding shaft is urged in the webbing winding direction by these springs. Further, a pawl lever is arranged near the gear spring so that the pawl lever can be engaged with the gear spring to prevent its rotation. This pawl lever operates in conjunction with the operation of the solenoid or the opening and closing of the vehicle door.

After the occupant wears the webbing, the pawl lever is actuated by the above-described actuating mechanism to prevent the gear spring from rotating. Therefore, the biasing force of the strong spring in the webbing winding direction does not act on the winding shaft, and the webbing is pulled only by the weak spring. Therefore, the occupant is put on the webbing without pressure. On the other hand, when the occupant releases the webbing, the pawl lever releases the rotation inhibition of the gear spring. Therefore, the urging force of the strong spring in the webbing winding direction acts on the winding shaft, and the webbing is quickly wound by the strong spring.

By the way, in the webbing retractor having such a tension reducer, when the webbing is fully wound up, as shown in FIG. It has been tightened). Then, when the tension reducer is operated after the webbing is pulled out, that is, when the rotation of the gear spring to which the outer end portion 62 of the weak spring spring 60 is connected is blocked by the pawl lever, the whole winding is closely attached. The biasing force of the weak spring 60 in the above state in the webbing winding direction acts on the winding shaft, and the winding shaft is rotated to release the biasing force.

In this case, in the weak spiral spring 60, the inner end portion 64 connected to the winding shaft releases the urging force while opening in the direction of arrow X in FIG. 66 rubbed against each other, which was a cause of abnormal noise and deterioration of operability due to frictional force.

[0006]

[Problems to be solved by the device]

 In consideration of the above facts, the present invention has an object to obtain a tension reducer capable of improving the operability by preventing generation of abnormal noise and frictional force during the operation of the tension reducer.

[0007]

[Means for Solving the Problems]

 The tension reducer according to the present invention is used in a webbing retractor that winds webbing around a take-up shaft in layers, and has a weak spring that is connected to the take-up shaft and a strong spring that has a larger biasing force than the weak spring described above. A connecting member that connects the weak spring and the strong spring in series and is rotatably arranged, and stops rotating in the webbing winding direction at a predetermined time when the webbing is pulled out from the winding shaft when the occupant wears the webbing. In the tension reducer including, the outer end portion of the weak spring spring described above is connected to the winding shaft, and the inner end portion of the weak spring spring is connected to the connecting member.

[0008]

[Action]

 In the tension reducer configured as described above, when the occupant pulls out and installs the webbing against the urging force of the strong and weak spiral springs connected in series, when the occupant is actuated, the rotation of the connecting member in the webbing winding direction is stopped. Therefore, the urging force of the strong spring in the webbing winding direction does not act on the winding shaft, and the webbing is pulled only by the weak spring. Therefore, the occupant is put on the webbing without pressure.

In this case, when the tension reducer is actuated and the rotation of the connecting member in the webbing winding direction is stopped, the urging force in the webbing winding direction of the weak spring spring, which is tightened by pulling out the webbing, is wound. This urging force is released by acting on the take-up shaft and rotating the take-up shaft.

Here, since the outer end of the weak spring is connected to the winding shaft, that is, the rotating side, and the inner end of the weak spring is connected to the connecting member, that is, the stopped side, the weak spring is wound. The urging force is released while spreading from the outer end side. Therefore, the adjacent side walls of the weak spiral spring do not rub against each other, and abnormal noise and frictional force are prevented from occurring, and the operability is improved.

When the occupant releases the wearing of the webbing and the tension reducer is released accordingly, the webbing take-up direction rotation of the connecting member becomes possible again. Therefore, the urging force of the strong spring in the webbing winding direction acts on the winding shaft again via the connecting member and the weak spring, and the webbing is quickly wound by the strong spring.

[0012]

【Example】

 FIG. 1 shows an exploded perspective view of a tension reducer 10 according to the present invention. Further, FIG. 2 shows a sectional view of a main part of the tension reducer 10, and FIG. 3 shows a schematic configuration diagram modeling the tension reducer 10.

In the tension reducer 10, the plate 12 is attached to a frame (not shown) of a webbing retractor to which the tension reducer 10 is applied. A through hole 14 is formed in the plate 12 coaxially with the webbing take-up shaft (axis line CL), and an adapter 16 is supported.

The adapter 16 has a substantially cylindrical shape, and a shaft portion 17 is formed on the plate 12 side. The shaft 17 is inserted into the through hole 14 of the plate 12 and rotatably supported, and is connected to the webbing take-up shaft. Therefore, the adapter 16 always rotates together with the webbing take-up shaft.

A notch 18 is cut in the inner periphery of the side wall of the adapter 16, and the outer end 20A of the weak spring spring 20 is engaged with the notch 18. The inner end 20B of the weak spring 20 is locked to a gear spring 32 as a connecting member.

The gear spring 32 is formed in a disk shape, and the ratchet teeth 34 are formed on the outer periphery thereof. Further, a shaft 33 is formed at the center of the gear spring 32 so as to project toward the adapter 16 along the axis CL. A cut portion 35 is cut in the shaft portion 33 along the axis, and the inner end portion 20B of the weak spring spring 20 is locked to the cut portion 35.

On the other hand, a shaft portion 36 is formed so as to project along the axis CL at the center of the gear spring 32 on the side opposite to the shaft portion 33. A notch 38 is cut in the shaft 36 along the axis, and an inner end 40A of a strong spring spring 40 is locked in the notch 38. The outer end 40B of the strong spring 40 is locked to the cover 42.

That is, as shown in FIG. 3, the adapter 16, the weak spring 20, the gear spring 32, and the strong spring 40 are configured to be connected in series, and the adapter 16 and the webbing take-up connected thereto. The shaft is biased in the webbing winding direction (the direction of arrow B in FIG. 1) by these two springs having a strong spring.

Below the gear spring 32, a pawl lever 50 that constitutes a rotation stopping means of the gear spring 32 is rotatably arranged. A pawl portion 52 is formed on the pawl lever 50 so that it can be engaged with the ratchet teeth 34 of the gear spring 32. When the claw portion 52 engages with the ratchet tooth 34, the rotation of the gear spring 32 in the webbing winding direction (the arrow B direction in FIG. 1) is blocked.

A return spring 54 is arranged near the pawl lever 50, and the pawl portion 52 of the pawl lever 50 is always biased in a direction away from the ratchet teeth 34. Further, a solenoid 56 is arranged near the pawl lever 50. The actuator portion 58 of the solenoid 56 is connected to the pawl lever 50, and when actuated, the pawl lever 50 is rocked and rotated against the biasing force of the return spring 54 so that the pawl portion 52 is engaged with the ratchet tooth 34. You can do it. The solenoid 56 operates when the occupant wears the webbing.

Next, the operation of this embodiment will be described. In the tension reducer 10 having the above-described configuration, before the occupant wears the webbing, that is, in a state where the webbing is fully wound up, as shown in FIG. 4 (A), the weak spring 20 is in a tightly wound state. Further, the strong spiral spring 40 is in a state in which the diameter is maximized. Therefore, in this state, the webbing can be freely pulled out by rotating the adapter 16 (winding shaft) against the urging force of the strong spiral spring 40.

When the occupant wears the pulled-out webbing, the solenoid 56 operates. When the solenoid 56 is actuated, the pawl lever 50 swings and rotates due to the movement of the actuator portion 58, the pawl portion 52 engages with the ratchet teeth 34 of the gear spring 32, and the gear spring 32 in the webbing winding direction. Rotation is blocked. Therefore, as shown in FIG. 4 (C), the strong spiral spring 40 is held as it is in a tightly wound state, and the urging force of the strong spiral spring 40 in the webbing winding direction is applied to the adapter 16 and the webbing take-up connected to the adapter 16. It does not act on the shaft and the webbing is pulled only by the weak spring spring 20. Therefore, the occupant is put on the webbing without any feeling of pressure.

In this case, when the tension reducer is activated and the rotation of the gear spring 32 in the webbing winding direction is stopped, the biasing force of the weak mainspring 20 in the webbing winding direction, which has been in close contact with all the windings, is applied. This urging force is released by acting on the adapter 16 (winding shaft) and rotating the winding shaft.

Here, the outer end portion 20A of the weak spring spring 20 is connected to the adapter 16 (winding shaft), that is, the rotating side, and the inner end portion 20B of the weak spring spring 20 is stopped by the gear spring 32, that is, stopped. Since the weak spring spring 20 is connected to the open side, the biasing force of the weak spring 20 is released while spreading from the side of the outer end 20A as shown in FIG. 4 (C). Therefore, the adjacent side walls of the weak spring spring 20 do not rub against each other, and abnormal noise and frictional force are prevented from occurring, and the operability is improved.

In the tension reducer operating state, the webbing can be pulled out only against the biasing force of the weak spring spring 20, that is, between the state shown in FIG. 4 (B) and the state shown in FIG. 4 (C). The webbing take-up shaft connected to the adapter 16 can also freely rotate, and the webbing withdrawal and operability are not hindered.

When the occupant releases the attachment of the webbing and the solenoid 56 is turned off (released) accordingly, the pawl lever 50 is swung by the urging force of the return spring 54, and the pawl portion 52 moves from the ratchet teeth 34. The gear spring 32 is separated and the rotation prevention of the gear spring 32 is released. Therefore, the urging force of the strong spring 40 in the webbing winding direction acts on the webbing winding shaft via the gear spring 32, the attachment 22, the weak spring 20 and the adapter 16, and the webbing has a large force. It is quickly wound up by the forces. Further, the strong spiral spring 40 returns to the state in which the diameter is maximized.

[0027]

[Effect of the device]

 As described above, the tension reducer according to the present invention has an excellent effect that the generation of abnormal noise and frictional force during the operation of the tension reducer is prevented and the operability can be improved.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a tension reducer according to the present invention.

FIG. 2 is a cross-sectional view of a main part of a tension reducer.

FIG. 3 is a schematic configuration diagram modeling a tension reducer.

4A to 4C are schematic front views showing a tightly wound state of a weak spiral spring and a strong spiral spring.

FIG. 5 is a schematic front view showing a tightly wound state of a weak spiral spring of a conventional tension reducer.

[Explanation of symbols]

 10 Tension Reducer 16 Adapter 20 Weak Spring Spring 20A Outer End 20B Inner End 32 Gear Spring (Coupling Member) 40 Strong Spring 50 Pawl Lever 56 Solenoid

Claims (1)

[Scope of utility model registration request] 1. A weak spring spring, which is used in a webbing winding device that winds webbing around a winding shaft in layers, is connected to the winding shaft, a strong spring having a larger urging force than the weak spring, and the weak spring. A connecting member that connects the mainspring and the strong spring in series and is rotatably arranged, and stops rotating in the webbing winding direction at a predetermined time when the webbing is pulled out from the winding shaft when the occupant wears the webbing. In the tension reducer, the outer end of the weak spring is connected to the winding shaft, and the inner end of the weak spring is connected to the connecting member.